The bundled products approach does not quite fit what I need here:

I need to hide a product always, EXCEPT if I call it in a link.
For instance in the product description of product A I will place a link to product B. But product B cannot appear anywhere until that link I place calls it. If that link to product B is clicked, then the product needs to appear as normal on the product_info page, and subsequently on all the cart view and checkout pages. (http://oshoboulder.org/store)

Any ideas on how to do that?

thanks,
JSC